Abstract : The report discusses procedures for preparation of horizontal construction joints using a high-pressure water jet, to compare these procedures with the alternative practice of wet sand-blasting, and to develop additional information on procedures and methods that have been used in horizontal construction joint practice. The investigation is divided into two phases, laboratory and field. One 6-in. maximum size crushed limestone aggregate concrete mixture, with a cement content of 235 lb/cu yd, an air content of 6 plus or minus percent, and a slump of 2 plus or minus 1/2 in. on the portion of the mixture passing the 1-1/2-in. sieve, was used to cast specimens for both phases. (Modified author abstract)